1. Field of the Invention
The present invention relates to message barring technology, and more particularly, to a method and system of message barring across mobile networks.
2. Description of the Related Art
FIG. 1 is a diagram of the architecture of a conventional GSM network for short message service (SMS). The architecture includes mobile stations (MSs) 11, 12, message switching centers (MSCs) 13, 16, a short message switching center (SMSC) 14, a home location register (HLR) 15, and a visit location register (VLR) 17. The MSC 13 connects multiple base stations (not shown) to receive short messages from the MS 11. When the MS 11 sends a short message (SM) to the MS 12, the SM is first transmitted to the SMSC 14 via the MSC 13. The HLR provides a database storing all MS (i.e., subscriber) profile information and service configuration information for each MS in GSM network for SMS authentication. The SMSC 14, the kernel device for SMS, stores the SM temporarily, authenticates the MS 12 by interrogating the HLR 15, and transmits the SM to the MSC 16 until the MS 12 is active within a time period; otherwise, time-out control is executed. The VLR 17 provides a database storing base station information in which the MS 12 is registered, thus enabling the MSC 16 to transmit MS to the MS 12 via the relevant base station (not shown).
FIG. 2 is a diagram of conventional GSM communication of SMS. When the MS 11 sends an SM to the MS. 12, a transmission request 21 with the SM, a source telephone number and a destination telephone number is transmitted to the SMSC 14 via the MSC 13. The SMSC 14 authenticates the MS 12 by interrogating the HLR 15, acquires routing information 22 upon successful authentication, and accordingly transmits the SM, the origin telephone number and the destination telephone number to the MSC 16. The MSC 16 acquires register information 23 by querying the VLR 17, and accordingly transmits the SM, the source telephone number and the destination telephone number to the MS 12. A transmission complete message is sequentially transmitted to the SMSC 14, MSC 13 and MS 11 upon successfully receipt of the SM by the MS 12.
Supplementary services have been used to enable or disable certain communication services including the SMS. MS ability to send/receive SM is configured through supplementary services, the configuration stores in the HLR 15. Although the SM can be barred by disabling SM receiving service, the SM is still received when the MS 12 is attached in a GPRS network. FIG. 3 is a flowchart showing a conventional method for routing information response. The process begins in step S31 to receive a routing information request. Step S32 determines whether the MS 12 has disabled the SM receiving service, and if so, the process proceeds to step S34; otherwise, the process proceeds to step S33 to transmit GSM routing information. Step S34 determines whether the MS 12 has registered GPRS services, and if so, the process proceeds to step S36 to transmit GPRS routing information; otherwise, the process proceeds to step S35 to transmit an error message. Similarly, although the SM can be barred by disabling SM sending service, the SM is still sent when the MS 11 is attached in GPRS network.
In view of these limitations, a need exists for a system and method of SM barring that avoids SM transmission via the GPRS network.